Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.

User Name:

Password

Please enter a password for your user account. Note that passwords are case-sensitive.

Password:

Confirm Password:

Email Address

Please enter a valid email address for yourself.

Email Address:

Log-in

User Name

Remember Me?

Password

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Additional Options

Miscellaneous Options

Automatically parse links in text

Automatically embed media (requires automatic parsing of links in text to be on).

Automatically retrieve titles from external links

Topic Review (Newest First)

10-16-2008 01:45 PM

oldbogie

Quote:

Originally Posted by Spankdaddy

Ive got a sbc with hairline cracks in the lifter valley across each cylinder water jacket. These showed up when magnafluxed. They showed no signs of leakage when the motor was torn down. I hate to get rid of the block because it is out of my anniversary model corvette. Can this be repaired and how expensive is it?

This is pretty common, if you chased every crack in a casting you'd go nuts. If they're not leaking and you don't lean on the engine for lots of power all the time, just ignore them.

Bogie

10-16-2008 01:11 PM

CNC BLOCKS NE

Quote:

Originally Posted by Irelands child

This is the website that I think will have the info that barnym has said will work:

One point everyone is ignoring is the engine was running fine and not leaking. How likely are the hairline cracks to begin leaking after a rebuild? How likely are they to get longer, larger and begin to leak years down the road? Just asking, as I stay as far away as possible from later SBC.

thnx, jack vines

10-16-2008 09:56 AM

Irelands child

Quote:

Originally Posted by barnym17

Check into lockstich crack repair this is a common repair for this condition.

This is the website that I think will have the info that barnym has said will work:

I do agree that unless this engine is not serial numbered to the car, that a replacement block is the way to go.

Dave W

10-16-2008 09:25 AM

6426yy

What year of corvette are we talking? If it needs decked chances are there gonna remove the VIN anyway. Find a block with the same casting #'s have it decked to 9.000" and no one will know the differance.

10-16-2008 09:00 AM

barnym17

Check into lockstich crack repair this is a common repair for this condition.

10-15-2008 10:03 PM

dt196

Actually, if it's the original motor out of his Corvette as he implies, it IS serialized to that car. But I do agree that it would be better to just replace it. By the way, which "anniversary" year is it?

10-15-2008 08:57 PM

4 Jaw Chuck

Toss it and don't look back, SBC's are a dime a dozen...its not like this one is serialized to your vehicle anyway.

10-15-2008 08:49 PM

BOBCRMAN@aol.com

I have seen quite a few of the later one piece rear seal blocks stress crack above the lifter bores. Usually toward the rear and up a couple inches. Running at an angle across the surface.

I have drilled the ends of the cracks, V-eed these cracks out, heated the block to about 500 degrees and welded the blocks. But, this is not something most shops can do. Also a bit spendy if you have a blacksmith do it.

Another block would be cheaper, unless you really need the matching numbers

10-15-2008 08:38 PM

scholman

Spankdaddy,

These cracks are from the block freezing in cold weather. I would not try to fix this because when you tighten the head bolts these cracks will pull apart and leak. I understand you want to keep the block but it is not worth throwing money at, just to have it leak at a later time causing more ruined parts and more down time. Junk it and find another block.

Sorry
Scholman

10-15-2008 08:22 PM

Spankdaddy

Cracks in lifter valley

Ive got a sbc with hairline cracks in the lifter valley across each cylinder water jacket. These showed up when magnafluxed. They showed no signs of leakage when the motor was torn down. I hate to get rid of the block because it is out of my anniversary model corvette. Can this be repaired and how expensive is it?